Chronic insomnia is reported by 10 percent of the population and a large percentage report self-medication using alcohol. Our preliminary data indicate that insomniacs are more likely to self-administer ethanol before bedtime than are non-insomniacs despite similar levels of moderate to light daytime social drinking. However, there is no information regarding the effects of ethanol on the sleep of insomniacs and the data regarding ethanol effects in normals and in alcoholics have used high ethanol doses and may not generalize to insomniacs. Critically, there is no information about the reinforcing properties of ethanol when self administered at bedtime by insomniacs. Do insomniacs use ethanol before sleep to improve their sleep, mood, or both and does that in turn increase daytime ethanol intake? Three experiments are proposed. They will employ standard sleep laboratory methods to diagnose insomnia and document the effects of ethanol on sleep and will use behavioral self-administration and subjective mood and drug effect assessments to determine the reinforcing and subjective effects of ethanol in insomniacs. During the first year, the study will focus on the question of whether, at what doses, and for how long ethanol has effects on sleep and mood. In year two, the study will assess how hypnotic ethanol self administration in insomniacs relates to ethanol dose, duration of nightly effects, and to the presence of an insomnia complaint versus an objective sleep disturbance. In the last two years, the grant focus will be on the extent to which hypnotic ethanol self-administration generalizes to daytime ethanol use.